#include <iostream>

using namespace std; 

int main()
{
	double k, d, sum=0; 
	int n; 
	cin>>k; 
	for (n=1; ;n++) {
		d = (double)n;
		sum += 1./d; 
		if (sum>k) 
			break; 
	}
	cout<<n; 
	return 0; 		
}

